Thought of something else
. Your first few BMs are going to be D and dark with old blood and mucus (kind of a rusty color). Don't be alarmed! It will be like this for 2 or 3 days. Today was the first day that I had a normal colored BM, and it's also starting to get formed again. Today was also the first day I could pass gas without stool. I know, TMI!
EDIT: My dad was the one that warned me about
this. He said when he saw all that blood, he thought that was it, the surgery failed and he was going to die (they gave him a 50/50 chance of living). He was in pretty bad shape though, so the average person may not have such an alarming BM.